It is a book about Christmas but there’s not a manger, virgin birth or angel in sight.

Buoyed by the success of their campaign which proclaimed There’s Probably No God, Now Stop Worrying on the side of London buses, some of Britain’s most prominent atheists have come together to publish a book for the festive season.

Due for publication this Friday, the book is already ranked at number 40 in the chart compiled by online retailer Amazon and could be a surprise bestseller.

Brooker asks whether a notional God would have a sense of humour, while there also chapters on the Hadron Collider and A Guide to Turning Your Home Into A Festive Something That Is So Bright It Can Be Seen From Space.

Writer Ariane Sherine, who masterminded and launched the atheist bus campaign on a Guardian Comment is Free post, said she was daunted by the idea of writing a book by herself, so enlisted the help of friends and supporters. “Virtually all the comedians I know are atheists and Richard Dawkins was very involved with the bus campaign,” she said.

Half of the profit will be donated to the Terrence Higgins Trust, the charity that deals with HIV issues. “Given some of the comments the Pope made earlier this year about condoms and Aids, we thought it was appropriate,” Sherine said.

She denies the book is anti-Christmas: “I wanted to make it clear that it’s a friendly, quite a happy book. I’ve sent it to some of my religious friends. The book is not just about being atheist – there’s a chapter on how to get on with relatives and ideas for party games.”

“Everyone has the right to freedom of thought, conscience and religion,” says the Human Rights Act. This freedom includes “the right to manifest his (or her) religion or belief in worship, teaching, practice and observance.”

That’s a fine aspiration but of course the Human Rights Act (HRA) isn’t all it’s cracked up to be by its supporters. Take the recent case of a 54-year-old nurse facing disciplinary action for wearing her confirmation cross, she was forced to accept an offer of redeployment to a non-nursing role at the Royal Devon and Exeter Hospital.

Although she had worn the cross throughout her 30 year service and no problems had been recorded, it was deemed to be a breach of uniform policy and – absurdly – a risk to health and safety, which of course trumps anything as elementary as the right to express your religious belief.

The trust made use of the second part of section nine of the HRA.

“Freedom to manifest one’s religion or beliefs shall be subject only to such limitations as are prescribed by law and are necessary in a democratic society in the interests of public safety, for the protection of public order, health or morals, or for the protection of the rights and freedoms of others.”

Shirley Chaplin had an impeccable record of service as a nurse. It is astonishing that the Devon and Exeter Trust would think of using their power in this way. But it seems the Human Rights Act is incapable of protecting the Shirley Chaplin’s of the world from the martinets and busybodies that infest public services and local authorities.

In Camden, London, a Christian group has been banned from displaying a notice in libraries and community centres advertising a talk on climate change because it mentioned Christianity and God. One poster said “Climate Change is a Christian Issue” . The ban puzzled the people at Roman Catholic Our Lady of Help of Christians parish church because they were told that they could display climate change posters that did not refer to God.

Naturally, the church is unlikely to take this to the law in order to test a policy that forbids the promotion of religious ideas, it almost certainly has neither the money nor the time for such frivolity. And so the injustice stands. But if Britain had a bill of rights that entrenched religious freedom and expression and made their suppression illegal then things would be rather different.

One of the problems with the law as it stands is that it is not applied equally. And there seems also to be some kind of agenda at work, laws are used to enforce a sterile secularity in ordinary behaviour and expression. One of the most disturbing cases I have heard of is the decision by the Crown Prosecution Service to bring a prosecution against a Christian couple that own hotel in Aintree, Liverpool.

Ben and Sharon Vogelenzang were arrested after a Muslim woman staying at their hotel complained to police about comments they made during a religious argument over breakfast. They have been charged under public order laws with using “threatening, abusive or insulting words… that were religiously aggravated”. Reports suggest that the couple said that prophet Muhammad , the founder of Islam, was a warlord and that the traditional Muslim dress for women was form of bondage.

You may, or may not agree, with these sentiments but surely they don’t merit a prosecution in a society where a good deal of latitude shown to the racism and homophobia preached by some imams. I can’t comment on the exact details of what the couple may have said, or their manner, or the offence taken by the customer but I can say that free speech – even about religion – is the freedom to be offended, and that the decision to prosecute is about as daft as it gets.

I hope that every organisation now happily ensconced in London’s spanking new Free Word centre understands that this case is critical to the freedom of all expression and that they send representatives en masse to support the couple when they appear in court in December.